Invitations will now be sent to people aged 55-64, starting with the oldest, according to a press release sent out by the ministry on Monday evening.

Since the AstraZeneca vaccine is not being used on those aged over 65, i.e. in phase 2 of the vaccination plan, the ministry confirmed on Monday that they would concurrently begin phase 5a. This will see those aged 55-64 being sent invitations to receive the vaccine, starting with the oldest.

This is decision was made based on an opinion published by the superior council of infectious disease (CSMI) on February 4, which stated that while the AstraZeneca vaccine is effective in terms of preventing severe forms of infection and by extension death, data on its efficacy for people "beyond a certain age" was limited at that time. These considerations led to the recommendation that MRNA vaccines from e.g. BioNTech/Pfizer and Moderna be used for people aged 65 and over, while younger cohorts can be given the AstraZeneca vaccine.

For more information on how the different vaccination types work, see the excellent Your Voice submission by Dr Angela Marley, or our recent PISA video.